1. Field of the Invention
The invention generally relates to controlling bleeding from severed or damaged peripheral blood vessels that are located in an area where it is difficult to apply conventional compression, such as the abdomen, pelvic or groin region. In particular, the invention provides a portable, small-footprint device with inflatable bladders that can be selectively positioned and inflated to exert pressure over peripheral blood vessels to stop exsanguination. In addition, the device may be used to assist in increasing perfusion pressure to the heart and brain in a number of disease sates such as hemorrhagic shock, cardiogenic shock, and cardiac arrest.
2. Background of the Invention
Hemorrhage from vascular injuries in the proximal extremities, pelvis, and abdomen is extremely difficult to treat. While the treatment of such injuries is challenging when they occur in civilian populations, they are even more difficult to treat in combat situations. While improvements in body armor have reduced mortality from combat injuries to the chest, the incidence of penetrating injuries to the extremity and their associated mortality remain high. It has been estimated that a well-designed battlefield tourniquet could potentially prevent 10% of all combat deaths due to exsanguinating peripheral vascular wounds. While it is gratifying that recent robust efforts have developed to create better tourniquets for treatment of these wounds, there remains a very important subset of lower extremity wounds in the region of the groin that cannot be treated with traditional tourniquets. Although the exact percentage of these wounds are unknown, both military and civilian reports detail the challenges in controlling ongoing hemorrhage of vascular injuries in this anatomical area especially in the pre-surgical time period.
Clearly, wounds to the groin, pelvis, and abdomen are complex and may involve several systems either alone or in combination, including major vascular structures, the bony pelvis, solid organs such as the liver and spleen, and even hollow organ injury to the bowel and bladder. Wounds directly involving isolated major vascular structures above the level of the femoral artery and vein such as the iliac artery and veins are most challenging to deal with followed by complex bony pelvic injuries from high velocity penetrating trauma resulting in complex arterial and lower pressure venous bleeding similar to those of blunt pelvic injuries experienced in a civilian trauma center.
Lastly even injuries involving isolated major vascular injury at or just above the inguinal ligament pose a tremendous field challenge in creating hemostasis. The femoral artery is usually palpable at the level of the inguinal ligament. Despite this, the ability to control bleeding by application of direct pressure by either the injured combatant or by others including fellow soldiers or medic aides will usually not suffice especially if rapid manual transport must take place. Controlling hemorrhage by application of direct manual pressure may be particularly challenging in cases where there is no large tissue defect allowing for packing and more pressure in closer proximity to the injured vessels. In fact, currently the only way to address this is by exploring the wound site, locating the artery and clamping it with hemostats. For deeper vascular injuries to the pelvis and abdomen, exploration is not an option until the time of surgery.
Similarly, cardiopulmonary resuscitation (CPR) to “restart” the heart of an injured patient is frequently necessary in emergency situations. During the period of time when a heart is not beating, and until it regains the ability to do so, it is imperative that respiration (i.e. lung inflation and deflation) be maintained so that blood circulation continues. It is especially essential to maintain blood circulation to the heart and brain during this time, or serious irreversible damage can occur. Even when a trained first aid provider performs chest compressions is these circumstances, blood flow in the victim is still well below normal (e.g. 20-30%). Thus, there is an ongoing need to provide adjunct therapies and devices that can aid in maintaining adequate blood flow during emergency situations that require CPR. In particular, it would be of benefit to have available a low-cost, portable, small footprint device that could be rapidly utilized in a straight forward manner. It would be especially desirable to have available a device with these attributes that could be used for both 1) the control of bleeding and 2) as an aid to CPR.
U.S. Pat. No. 3,933,150 to Kaplan et al. teaches an apparatus for the treatment of shock. The apparatus includes a single piece of double-walled material that can receive pressurized gas. Inflation of the device causes pressure to be exerted on an individual wearing the apparatus, thereby decreasing the volume of pooled venous blood and stabilizing the individual during transport. However, the pressure is exerted is globally or circumferentially and is not specifically directed onto the bleeding site, and thus does little for bleeding from locations that are difficult to access.
U.S. Pat. No. 7,329,792 to Buckman et al., discloses an apparatus for promoting hemostasis, especially of skin-penetrating wounds of the periphery. The device includes fluid impermeable barriers surrounded by exterior dams to be held in place over a wound by applied force. However, such devices are not suited to promote hemostasis in regions that are difficult and thus where it is difficult to exert pressure.
U.S. Pat. No. 6,939,314 to Hall et al. teaches an automatic chest compression system, for example, during CPR. The system utilizes a bladder that is comprised of a plurality of individual sections that are preferentially in fluid communication with each other. When the bladder is disposed over the sternum of a patient and inflated (e.g. with a gas or fluid), pressure is exerted on the chest of the patient. However, the positions of the sections of the bladder are fixed with respect to each other and thus the device does not provide flexibility with respect to positioning of the bladder sections. This device would not be suitable for use, for example, to control bleeding in regions where it is difficult to exert pressure, such as the groin.
U.S. Pat. No. 5,743,864 to Baldwin discloses an apparatus for performing cardio-pulmonary resuscitation with active reshaping of a patient's chest. However, the apparatus requires a piston as the driving force for compression, and is clearly not designed for easy storage and transport for use in the field, and the technology is not transferable to use in controlling bleeding in regions where it is difficult to exert pressure.
The prior art has thus far failed to provide a device to aid in the temporary isolation and occlusion of an artery by the application of precisely directed pressure. In particular, the prior art has not provided a device that can be so-used that can also be employed as an adjunct to provide chest compression during CPR.